RepoMed (Medizinische Hochschule Hannover)
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Time is crucial in malignant tumor cases: speeding up the process of patient-specific implant creation
Get PDFPurpose Patient-specific implants are commonly used to reconstruct lower jaw defects following surgical treatment for head and neck squamous cell carcinoma. The planning process of surgery is time-consuming and can delay the "time to surgery," which should be as short as possible. Therefore, this study aimed to evaluate the planning process to speed up and identify any sources of problems. Patients and methods In this retrospective study, we enrolled patients who underwent continuous resection of the mandible in combination with reconstruction with a patient-specific implant between 2016 and 2021. The predictor variables were in-house training of the engineers and implant complexity (complex [with additional features] vs. less complex [resembling standard reconstruction plates]). The outcome variables were the duration of communication, message length, and the need for synchronous communication or modifications to the original design. Descriptive and univariate statistics were computed, and statistical significance was set at P < 0.05. Results The data from 83 patients were included in this study. The mean duration of communication was 14.05 ± 13.58 days. The implant complexity and training status of the engineer had no statistically significant influence on the primary outcome variables. As for the secondary outcome variables, the implant complexity significantly influenced the chance that the planned operation had to be postponed (15/16 [93.75%] were complex cases, P = 0.001). The most frequent cause of problems in the planning process was an insufficient dataset, which was not dependent on the type of imaging. Conclusions The overall duration of the patient-specific implant creation process is too long to meet oncological requirements. Therefore, standardization of the planning process to accelerate implant creation is of utmost importance. In addition, a common standard imaging format (independent of the type of imaging) for oncological cases could eliminate all delays caused by insufficient datasets in the future
Transcriptional bursts and heterogeneity among cardiomyocytes in hypertrophic cardiomyopathy
Get PDFTranscriptional bursting is a common expression mode for most genes where independent transcription of alleles leads to different ratios of allelic mRNA from cell to cell. Here we investigated burst-like transcription and its consequences in cardiac tissue from Hypertrophic Cardiomyopathy (HCM) patients with heterozygous mutations in the sarcomeric proteins cardiac myosin binding protein C (cMyBP-C, MYBPC3) and cardiac troponin I (cTnI, TNNI3). Using fluorescence in situ hybridization (RNA-FISH) we found that both, MYBPC3 and TNNI3 are transcribed burst-like. Along with that, we show unequal allelic ratios of TNNI3-mRNA among single cardiomyocytes and unequally distributed wildtype cMyBP-C protein across tissue sections from heterozygous HCM-patients. The mutations led to opposing functional alterations, namely increasing (cMyBP-Cc.927-2A>G) or decreasing (cTnIR145W) calcium sensitivity. Regardless, all patients revealed highly variable calcium-dependent force generation between individual cardiomyocytes, indicating contractile imbalance, which appears widespread in HCM-patients. Altogether, we provide strong evidence that burst-like transcription of sarcomeric genes can lead to an allelic mosaic among neighboring cardiomyocytes at mRNA and protein level. In HCM-patients, this presumably induces the observed contractile imbalance among individual cardiomyocytes and promotes HCM-development
Langzeit-Ergebnisse nach intraoperativer extrakorporaler Membranoxygenierung während der Lungentransplantation
Get PDFAktuelle Entwicklung von Krankheitserregern und Antibiotikaresistenzen bei Patient:innen mit dekompensierter Leberzirrhose
Get PDFHepatitis A Immunity and Paediatric Liver Transplantation: A Single-Centre Analysis
Get PDFFollowing paediatric solid organ liver transplantation, risk of infection is high, both in the short and long term. Even though an infection with hepatitis A virus (HAV) is often asymptomatic and self-limited in children, some case studies describe severe cases leading to death. Vaccinations offer simple, safe and cheap protection. However, data on vaccination rates against hepatitis A in children with liver disease are scarce. Moreover, the vaccine is only approved from the age of one year old. At the same time, up to 30% of children with liver disease are transplanted within the first year of life, so the window of opportunity for vaccination is limited. This retrospective, observational, single-centre study examines the HAV immunity in paediatric liver transplant recipients before and after the first year of transplantation. Vaccination records of 229 of 279 (82.1%) children transplanted between January 2003 and June 2021 were analysed. Of 139 eligible children aged ≥ 1 year old, only 58 (41.7%) were vaccinated at least with one HAV dose prior to transplantation. In addition, seven patients received the vaccine below one year of age. After one or two doses, 38.5% or 90.6% of 65 patients were anti-HAV-IgG positive, respectively. This percentage remained stable up to the first annual check-up. For children vaccinated only once, a shorter interval from vaccination to transplantation is a risk factor for lack of immunity. Thus, HAV immunisation should be started earlier in liver transplant candidates to improve immunity in this high-risk group
Charakterisierung von thromboembolischen Komplikationen im Langzeitverlauf nach Fontan-Operation
Get PDFOpen latarjet procedure versus all-arthroscopic autologous tricortical iliac crest bone grafting for anterior-inferior glenohumeral instability with glenoid bone loss.
Get PDFPurpose The purpose of this study is to compare the open Latarjet procedure versus the all-arthroscopic autologous tricortical iliac crest bone grafting (AICBG) technique for recurrent anterior-inferior glenohumeral instability with glenoid bone loss. Methods All open Latarjet and AICBG procedures for recurrent anterior-inferior shoulder instability with glenoid bone loss performed at two institutions between September 2015 and April 2019 were retrospectively analyzed. Inclusion criteria were a traumatic etiology, a glenoid surface deficiency >13.5%, and a minimum follow-up (FU) of 18 months. Primary outcomes included the subjective shoulder value, the Western Ontario Shoulder Instability (WOSI), Rowe scores including subdomains, and the four subdomains of the Constant score (pain, activities of daily living, internal rotation, external rotation). Secondary outcomes were subjective shoulder instability, EQ-5D-3 L, pain level on the VAS, level of overall satisfaction, operative time, return-to-work rate, and return-to-sports rate. Results Forty-three patients were available for final analysis (Latarjet: n = 21; AICBG: n = 22) at an average FU of 34.9 months (range, 22-66 months). Both techniques provided good outcomes and improved stability. The Rowe score, Rowe-range of motion, and CS-internal rotation (p = 0.008, p<0.001, p = 0.001) were slightly better in the AICBG group. Furthermore, the WOSI physical symptoms subdomain was significantly better (p = 0.04) in the AICBG group, while its total score did not reach statistical significance (p = 0.07). There was no statistically significant difference in the secondary outcomes besides operative time, which was significantly shorter in the Latarjet procedure group (p = 0.04). Overall complication rate was similar in both groups (Latarjet: 9.5% (n = 2), AICBG: 9.1% (n = 2)). Conclusion Open Latarjet and AICBG procedures provide comparable clinical outcomes except for significantly better Rowe score, Rowe-range of motion, WOSI physical symptoms subdomain, and internal rotation capacity in the AICBG group. However, these results should be carefully interpreted in the context of known minimal clinically important differences of these scores
Different Acute Kidney Injury Patterns after Renal Ischemia Reperfusion Injury and Extracorporeal Membrane Oxygenation in Mice.
Get PDFThe use of extracorporeal membrane oxygenation (ECMO) is associated with acute kidney injury (AKI) in thoracic organ transplantation. However, multiple other factors contribute to AKI development after these procedures such as renal ischemia-reperfusion injury (IRI) due to hypo-perfusion of the kidney during surgery. In this study, we aimed to explore the kidney injury patterns in mouse models of ECMO and renal IRI. Kidneys of C57BL/6 mice were examined after moderate (35 min) and severe (45 min) unilateral transient renal pedicle clamping and 2 h of veno-venous ECMO. Renal injury markers, neutrophil infiltration, tubular transport function, pro-inflammatory cytokines, and renal heme oxygenase-1 (HO-1) expression were determined by immunofluorescence and qPCR. Both procedures caused AKI, but with different injury patterns. Severe neutrophil infiltration of the kidney was evident after renal IRI, but not following ECMO. Tubular transport function was severely impaired after renal IRI, but preserved in the ECMO group. Both procedures caused upregulation of pro-inflammatory cytokines in the renal tissue, but with different time kinetics. After ECMO, but not IRI, HO-1 was strongly induced in tubular cells indicating contact with hemolysis-derived proteins. After IRI, HO-1 was expressed on infiltrating myeloid cells in the tubulo-interstitial space. In conclusion, renal IRI and ECMO both caused AKI, but kidney damage after renal IRI was more pronounced including severe neutrophil infiltration and tubular transport impairment. Enhanced HO-1 expression in tubular cells after ECMO encourages limitation of hemolysis as a therapeutic approach to reduce ECMO-associated AKI
Short-Term Supplementation of Sodium Nitrate vs. Sodium Chloride Increases Homoarginine Synthesis in Young Men Independent of Exercise
Get PDFThe aim of the study was to investigate the effects of short-term oral administration of inorganic nitrate (NaNO3; n = 8) or placebo (NaCl; n = 9) (each 0.1 mmol/kg body weight/d for 9 days) on plasma amino acids, creatinine, and oxidative stress in healthy young men. At baseline, the plasma concentrations of amino acids did not differ between the groups. At the end of the study, the plasma concentrations of homoarginine (hArg; by 24%, p = 0.0001), citrulline and ornithine (Cit/Orn; by 16%, p = 0.015), and glutamine/glutamate (Gln/Glu; by 6%, p = 0.0003) were higher in the NaNO3 group compared to the NaCl group. The plasma concentrations of sarcosine (Sarc; by 28%, p hArg + Orn, with equilibrium constant Kharg; (2) the formation of guanidinoacetate (GAA) and Orn from Arg and glycine (Gly): Arg + Gly GAA + Orn, with equilibrium constant Kgaa. The plasma Kgaa/KhArg ratio was lower in the NaNO3 group compared to the NaCl group (1.57 vs. 2.02, p = 0.0034). Our study suggests that supplementation of inorganic nitrate increases the AGAT-catalyzed synthesis of hArg and decreases the N-methyltransferase-catalyzed synthesis of GAA, the precursor of creatine. To our knowledge, this is the first study to demonstrate elevation of hArg synthesis by inorganic nitrate supplementation. Remarkably, an increase of 24% corresponds to the synthesis capacity of one kidney in healthy humans. Differences in the association between plasma concentrations of amino acids in the NaNO3 and NaCl groups suggest changes in amino-acid homeostasis. Plasma concentrations of the oxidative stress marker malondialdehyde (MDA) did not change after supplementation of NaNO3 or NaCl over the whole exercise time range. Plasma nitrite concentration turned out to be a more discriminant marker of NaNO3 ingestion than plasma nitrate (area under the receiver operating characteristic curve: 0.951 vs. 0.866, p < 0.0001 each)